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Equation governing the probability density evolution of multi-dimensional linear fractional differential systems subject to Gaussian white noise
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作者 Yi Luo Meng-Ze Lyu +1 位作者 Jian-Bing Chen Pol D.Spanos 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2023年第3期199-208,共10页
Stochastic fractional differential systems are important and useful in the mathematics,physics,and engineering fields.However,the determination of their probabilistic responses is difficult due to their non-Markovian ... Stochastic fractional differential systems are important and useful in the mathematics,physics,and engineering fields.However,the determination of their probabilistic responses is difficult due to their non-Markovian property.The recently developed globally-evolving-based generalized density evolution equation(GE-GDEE),which is a unified partial differential equation(PDE)governing the transient probability density function(PDF)of a generic path-continuous process,including non-Markovian ones,provides a feasible tool to solve this problem.In the paper,the GE-GDEE for multi-dimensional linear fractional differential systems subject to Gaussian white noise is established.In particular,it is proved that in the GE-GDEE corresponding to the state-quantities of interest,the intrinsic drift coefficient is a time-varying linear function,and can be analytically determined.In this sense,an alternative low-dimensional equivalent linear integer-order differential system with exact closed-form coefficients for the original highdimensional linear fractional differential system can be constructed such that their transient PDFs are identical.Specifically,for a multi-dimensional linear fractional differential system,if only one or two quantities are of interest,GE-GDEE is only in one or two dimensions,and the surrogate system would be a one-or two-dimensional linear integer-order system.Several examples are studied to assess the merit of the proposed method.Though presently the closed-form intrinsic drift coefficient is only available for linear stochastic fractional differential systems,the findings in the present paper provide a remarkable demonstration on the existence and eligibility of GE-GDEE for the case that the original high-dimensional system itself is non-Markovian,and provide insights for the physical-mechanism-informed determination of intrinsic drift and diffusion coefficients of GE-GDEE of more generic complex nonlinear systems. 展开更多
关键词 Globally-evolving-based generalized density evolution equation(GE-GDEE) Linear fractional differential system Non-Markovian system Analytical intrinsic drift coefficient Dimension reduction
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The Jaffa Transform for Hessian Matrix Systems and the Laplace Equation
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作者 Daniel A. Jaffa 《Journal of Applied Mathematics and Physics》 2024年第1期98-125,共28页
Hessian matrices are square matrices consisting of all possible combinations of second partial derivatives of a scalar-valued initial function. As such, Hessian matrices may be treated as elementary matrix systems of ... Hessian matrices are square matrices consisting of all possible combinations of second partial derivatives of a scalar-valued initial function. As such, Hessian matrices may be treated as elementary matrix systems of linear second-order partial differential equations. This paper discusses the Hessian and its applications in optimization, and then proceeds to introduce and derive the notion of the Jaffa Transform, a new linear operator that directly maps a Hessian square matrix space to the initial corresponding scalar field in nth dimensional Euclidean space. The Jaffa Transform is examined, including the properties of the operator, the transform of notable matrices, and the existence of an inverse Jaffa Transform, which is, by definition, the Hessian matrix operator. The Laplace equation is then noted and investigated, particularly, the relation of the Laplace equation to Poisson’s equation, and the theoretical applications and correlations of harmonic functions to Hessian matrices. The paper concludes by introducing and explicating the Jaffa Theorem, a principle that declares the existence of harmonic Jaffa Transforms, which are, essentially, Jaffa Transform solutions to the Laplace partial differential equation. 展开更多
关键词 Hessian Matrices Jacobian Matrices Laplace Equation Linear Partial differential Equations Systems of Partial differential Equations Harmonic Functions Incompressible and Irrotational Fluid Mechanics
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ESTIMATES FOR THE HYPER-ORDER OF SOLUTIONS OF CERTAIN LINEAR DIFFERENTIAL EQUATIONS 被引量:2
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作者 江良英 陈宗煊 《Acta Mathematica Scientia》 SCIE CSCD 2008年第2期393-400,共8页
In this article, the authors study the growth of certain second order linear differential equation f″+A(z)f′+B(z)f=0 and give precise estimates for the hyperorder of solutions of infinite order. Under similar ... In this article, the authors study the growth of certain second order linear differential equation f″+A(z)f′+B(z)f=0 and give precise estimates for the hyperorder of solutions of infinite order. Under similar conditions, higher order differential equations will be considered. 展开更多
关键词 Linear differential equation entire function HYPER-ORDER GENUS
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LIMITING DIRECTION AND BAKER WANDERING DOMAIN OF ENTIRE SOLUTIONS OF DIFFERENTIAL EQUATIONS 被引量:2
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作者 王珺 陈宗煊 《Acta Mathematica Scientia》 SCIE CSCD 2016年第5期1331-1342,共12页
In this paper, we mainly investigate entire solutions of complex differential equations with coefficients involving exponential functions, and obtain the dynamical properties of the solutions, their derivatives and pr... In this paper, we mainly investigate entire solutions of complex differential equations with coefficients involving exponential functions, and obtain the dynamical properties of the solutions, their derivatives and primitives. With some conditions on coefficients, for the solutions, their derivatives and their primitives, we consider the common limiting directions of Julia set and the existence of Baker wandering domain. 展开更多
关键词 limiting direction Baker wandering domain entire function linear differential equation
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LIMITING DIRECTIONS OF JULIA SETS OF ENTIRE SOLUTIONS TO COMPLEX DIFFERENTIAL EQUATIONS 被引量:1
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作者 王珺 陈宗煊 《Acta Mathematica Scientia》 SCIE CSCD 2017年第1期97-107,共11页
In this paper,we mainly investigate the dynamical properties of entire solutions of complex differential equations.With some conditions on coefficients,we prove that the set of common limiting directions of Julia sets... In this paper,we mainly investigate the dynamical properties of entire solutions of complex differential equations.With some conditions on coefficients,we prove that the set of common limiting directions of Julia sets of solutions,their derivatives and their primitives must have a definite range of measure. 展开更多
关键词 limiting direction Julia set entire function linear differential equation defi-ciency
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DETERMINING THE DISCRIMINATING DOMAIN FOR HYBRID LINEAR DIFFERENTIAL GAME WITH TWO PLAYERS AND TWO TARGETS 被引量:1
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作者 韩艳丽 高岩 《Acta Mathematica Scientia》 SCIE CSCD 2017年第6期1594-1606,共13页
This paper studies a bounded discriminating domain for hybrid linear differential game with two players and two targets using viability theory. First of all, we prove that the convex hull of a closed set is also a dis... This paper studies a bounded discriminating domain for hybrid linear differential game with two players and two targets using viability theory. First of all, we prove that the convex hull of a closed set is also a discriminating domain if the set is a discriminating domain. Secondly, in order to determine that a bounded polyhedron is a discriminating domain, we give a result that it only needs to verify that the extreme points of the polyhedron meet the viability conditions. The difference between our result and the existing ones is that our result just needs to verify the finite points (extreme points) and the existing ones need to verify all points in the bounded polyhedron. 展开更多
关键词 VIABILITY hybrid linear differential game discriminating domain nonsmoothanalysis
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ON GLOBAL MEROMORPHIC SOLUTIONS OF SECOND-ORDER LINEAR DIFFERENTIAL EQUATIONS WITH MEROMORPHIC COEFFICIENTS 被引量:1
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作者 孔荫莹 孙道椿 《Acta Mathematica Scientia》 SCIE CSCD 2013年第2期423-429,共7页
The main purpose of this article is to study the existence theories of global meromorphic solutions for some second-order linear differential equations with meromorphic coefficients, which perfect the solution theory ... The main purpose of this article is to study the existence theories of global meromorphic solutions for some second-order linear differential equations with meromorphic coefficients, which perfect the solution theory of such equations. 展开更多
关键词 Second-order linear differential equations global meromorphic solutions mero-morphic continuation
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Dynamic Deformation Monitoring of Lotsane Bridge Using Global Positioning Systems (GPS) and Linear Variable Differential Transducers (LVDT) 被引量:5
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作者 Selassie David Mayunga M. Bakaone 《Journal of Data Analysis and Information Processing》 2021年第1期30-50,共21页
The measurements and analysis of deformation of engineering structures such as dams, bridges and high-rise buildings are important tasks for civil engineers. It is evident that, all civil engineering structures are su... The measurements and analysis of deformation of engineering structures such as dams, bridges and high-rise buildings are important tasks for civil engineers. It is evident that, all civil engineering structures are susceptible for deterioration over a period of time. Bridges in particular, deteriorate due to loading conditions, environmental changes, earth movement, material used during construction, age and corrosion of steel. Continuous monitoring of such structure is the most important aspect as it provides quantitative information, assesses the state of the structure, detects unsafe positions and proposes early safety measures to be taken before it can threaten the safety of vehicles, goods and human life. Despite government’s efforts to construct roads and highways, bridge deformation monitoring has not been given priority in most of African countries and ultimately causes some bridges to collapse unexpectedly. The purpose of this research is to integrate Global Positioning System (GPS) and Linear Variable Differential Transducers (LVDT) to monitor deformation of a bridge. The horizontal positions of reference and monitoring points were determined using Global Positioning System (GPS) while the vertical deflections, accelerations and strain were determined using Linear Variable Differential Transducers (LVDT). The maximum displacements obtained between zero and first epochs in x, y and z components were 0.798 m, at point LT08, 0.865 m at point BR13, and 0.56 m at point LT02 respectively. The maximum deflections for LVDT 1, 2 and 3 are 28.563 mm, 31.883 mm and 40.926 mm respectively. Finally, the correlation coefficient for the observations was 0.679 with standard deviations of 0.0168 and 0.0254 in x and y respectively. Our results identified some slight displacements in horizontal components at the bridge. 展开更多
关键词 Bridge Deformation Monitoring GPS and Linear Variable differential Transducers
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Discrete differential evolution algorithm for integer linear bilevel programming problems 被引量:1
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作者 Hong Li Li Zhang Yongchang Jiao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第4期912-919,共8页
A discrete differential evolution algorithm combined with the branch and bound method is developed to solve the integer linear bilevel programming problems, in which both upper level and lower level variables are forc... A discrete differential evolution algorithm combined with the branch and bound method is developed to solve the integer linear bilevel programming problems, in which both upper level and lower level variables are forced to be integer. An integer coding for upper level variables is adopted, and then a discrete differential evolution algorithm with an improved feasibility-based comparison is developed to directly explore the integer solution at the upper level. For a given upper level integer variable, the lower level integer programming problem is solved by the existing branch and bound algorithm to obtain the optimal integer solution at the lower level. In the same framework of the algorithm, two other constraint handling methods, i.e. the penalty function method and the feasibility-based comparison method are also tested. The experimental results demonstrate that the discrete differential evolution algorithm with different constraint handling methods is effective in finding the global optimal integer solutions, but the improved constraint handling method performs better than two compared constraint handling methods. 展开更多
关键词 discrete linear bilevel programming problem discrete differential evolution constraint handling method branch and bound algorithm
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EXISTENCE OF MEROMORPHIC SOLUTIONS OF SOME HIGHER ORDER LINEAR DIFFERENTIAL EQUATIONS
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作者 张晓梅 孙道椿 《Acta Mathematica Scientia》 SCIE CSCD 2013年第2期600-608,共9页
This article discusses the problems on the existence of meromorphic solutions of some higher order linear differential equations with meromorphic coefficients. Some nice results are obtained. And these results perfect... This article discusses the problems on the existence of meromorphic solutions of some higher order linear differential equations with meromorphic coefficients. Some nice results are obtained. And these results perfect the complex oscillation theory of meromorphic solutions of linear differential equations. 展开更多
关键词 Higher order linear differential equation meromorphic coefficient meromorphicsolutions the first coefficient
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DIFFERENTIATOR SERIES SOLUTION OF LINEAR DIFFERENTIAL ORDINARY EQUATION
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作者 柯红路 谢和熙 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1999年第8期59-66,共8页
In this paper, the principle techinique of the differentiator method, and some examples using the method to obtain the general solution and special solution of the differential equation are introduced. The essential d... In this paper, the principle techinique of the differentiator method, and some examples using the method to obtain the general solution and special solution of the differential equation are introduced. The essential difference between this method and the others is that by this method special and general solutions can be obtained directly with the operations of the differentor in the differential equation and without the enlightenment of other scientific knowledge. 展开更多
关键词 linear ordinary differential equation differentiator series method special solution general solution
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INSTABILITY OF SOLUTION FOR THE FOURTH ORDER LINEAR DIFFERENTIAL EQUATION WITH VARIED COEFFICIENT
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作者 卢德渊 廖宗璜 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1993年第5期481-497,共17页
In this paper, we give some sufficient conditions of the instability for the fourth order linear differential equation with varied coefficient, at least one of the characteristic roots of which has positive real part,... In this paper, we give some sufficient conditions of the instability for the fourth order linear differential equation with varied coefficient, at least one of the characteristic roots of which has positive real part, by means of Liapunov's second method. 展开更多
关键词 ordinary differential equation motive stability theory linear differential equation with varied coefficient
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ON DETERMINATION OF THE IMPULSIVE SOLUTIONS AND IMPULSIVE PROPERTIES TO LINEAR NON-HOMOGENEOUS MATRIX DIFFERENTIAL EQUATIONS
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作者 谭连生 《Acta Mathematica Scientia》 SCIE CSCD 2000年第2期261-272,共12页
This note contains three main results. Firstly, a complete solution of the Linear Non-Homogeneous Matrix Differential Equations (LNHMDEs) is presented that takes into account both the non-zero initial conditions of th... This note contains three main results. Firstly, a complete solution of the Linear Non-Homogeneous Matrix Differential Equations (LNHMDEs) is presented that takes into account both the non-zero initial conditions of the pseudo state and the nonzero initial conditions of the input. Secondly, in order to characterise the dynamics of the LNHMDEs correctly,some important concepts such as the state, slow state (smooth state) and fast state (impulsive state) are generalized to the LNHMDE case and the solution of the LNHMDEs is separated into the smooth (slow) response and the fast (implusive) response. As a third result, a new characterization of the impulsive free initial conditions of the LNHMDEs is given. 展开更多
关键词 linear matrix differential equation impulsive and smooth solution impulsive free initial conditions {1}-inverse
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HARDY-LITTLEWOOD-POLYA INEQUALITY FOR A LINEAR DIFFERENTIAL OPERATOR AND SOME RELATED OPTIMAL PROBLEMS
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作者 陈迪荣 孙永生 《Analysis in Theory and Applications》 1992年第1期50-58,共9页
In this paper a generalized version of the classical Hardy-Littlewood-Polya inequality is given.Furthermore,the Stechkin's problem for a linear differential operator is solved in L_2(R), and the optimal recovery p... In this paper a generalized version of the classical Hardy-Littlewood-Polya inequality is given.Furthermore,the Stechkin's problem for a linear differential operator is solved in L_2(R), and the optimal recovery problem for such differential operator is considered. 展开更多
关键词 Th HARDY-LITTLEWOOD-POLYA INEQUALITY FOR A LINEAR differential OPERATOR AND SOME RELATED OPTIMAL PROBLEMS
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A HIGH ACCURACY DIFFERENCE SCHEME FOR THE SINGULAR PERTURBATION PROBLEM OF THE SECOND-ORDER LINEAR ORDINARY DIFFERENTIAL EQUATION IN CONSERVATION FORM
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作者 王国英 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第5期465-470,共6页
In this paper, combining the idea of difference method and finite element method, we construct a difference scheme for a self-adjoint problem in conservation form. Its solution uniformly converges to that of the origi... In this paper, combining the idea of difference method and finite element method, we construct a difference scheme for a self-adjoint problem in conservation form. Its solution uniformly converges to that of the original differential equation problem with order h3. 展开更多
关键词 A HIGH ACCURACY DIFFERENCE SCHEME FOR THE SINGULAR PERTURBATION PROBLEM OF THE SECOND-ORDER LINEAR ORDINARY differential EQUATION IN CONSERVATION FORM
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Experimental Behavior of Recycled Aggregate Concrete Filled Steel Tubular Columns
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作者 Thirumalai R Suresh Babu S 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第6期1414-1417,共4页
During the modernization or rehabilitation activity,the demolished structural waste causes large soil pollution and unavailability of natural aggregate is the big concern for the construction industry.Therefore,this m... During the modernization or rehabilitation activity,the demolished structural waste causes large soil pollution and unavailability of natural aggregate is the big concern for the construction industry.Therefore,this manuscript deals with the Composite Steel Circular Column(CSCC)with Recycled Aggregate concrete(RAC)as infill is partly used,with the replacement of 25%and 50%in M30 grade of Concrete.And internal reinforcement steel is fully replaced by rolled steel tubes(circular and square)with varied thickness,ISA-unequal angle.Around 14 specimens are cast and examined under axial load for analysis of the deflection characteristics,the load-bearing capacity along with its buckling behavior.The experimental values are estimated through LVDT(linear variable differential transducer)at 3-phase.The curve of load-deflection is drawn with the load pattern.From the date interpretation,it is found column made of 50%-RAC has more than 25%-RAC. 展开更多
关键词 composite steel circular column(CSCC) recycled aggregate concrete(RAC) ISAinternational standard angle LVDT(linear variable differential transducer)
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Nonlinear Conformal Gravitation
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作者 J.-F. Pommaret 《Journal of Modern Physics》 2023年第11期1464-1496,共33页
In 1909 the brothers E. and F. Cosserat discovered a new nonlinear group theoretical approach to elasticity (EL), with the only experimental need to measure the EL constants. In a modern framework, they used the nonli... In 1909 the brothers E. and F. Cosserat discovered a new nonlinear group theoretical approach to elasticity (EL), with the only experimental need to measure the EL constants. In a modern framework, they used the nonlinear Spencer sequence instead of the nonlinear Janet sequence for the Lie groupoid defining the group of rigid motions of space. Following H. Weyl, our purpose is to compute for the first time the linear and nonlinear Spencer sequences for the Lie groupoid defining the conformal group of space-time in order to provide the mathematical foundations of both electromagnetism (EM) and gravitation (GR), with the only experimental need to measure the EM and GR constants. With a manifold of dimension n ≥ 3, the difficulty is to deal with the n nonlinear transformations that have been called “elations” by E. Cartan in 1922. Using the fact that dimension n = 4 has very specific properties for the computation of the Spencer cohomology, we also prove that there is no conceptual difference between the (nonlinear) Cosserat EL field or induction equations and the (linear) Maxwell EM field or induction equations. As for gravitation, the dimension n = 4 also allows to have a conformal factor defined everywhere but at the central attractive mass because the inversion law of the isotropy subgroupoid made by second order jets transforms attraction into repulsion. The mathematical foundations of both electromagnetism and gravitation are thus only depending on the structure of the conformal pseudogroup of space-time. 展开更多
关键词 Nonlinear differential Sequences Linear differential Sequences Lie Groupoids Lie Algebroids Conformal Geometry Spencer Cohomology Maxwell Equations Cosserat Equations
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Model Predictive Control of Nonlinear Systems: Stability Region and Feasible Initial Control 被引量:5
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作者 Xiao-Bing Hu Wen-Hua Chen 《International Journal of Automation and computing》 EI 2007年第2期195-202,共8页
This paper proposes a new method for model predictive control (MPC) of nonlinear systems to calculate stability region and feasible initial control profile/sequence, which are important to the implementations of MPC... This paper proposes a new method for model predictive control (MPC) of nonlinear systems to calculate stability region and feasible initial control profile/sequence, which are important to the implementations of MPC. Different from many existing methods, this paper distinguishes stability region from conservative terminal region. With global linearization, linear differential inclusion (LDI) and linear matrix inequality (LMI) techniques, a nonlinear system is transformed into a convex set of linear systems, and then the vertices of the set are used off-line to design the controller, to estimate stability region, and also to determine a feasible initial control profile/sequence. The advantages of the proposed method are demonstrated by simulation study. 展开更多
关键词 Model predictive control (MPC) stability region terminal region linear differential inclusion (LDI) linear matrix inequality (LMI).
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A UNIFORMLY CONVERGENT FINITE DIFFERENCE METHOD FOR A SINGULARLY PERTURBED INITIAL VALUE PROBLEM
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作者 G. M. Amiraliyev, Hakk Duru Department of Mathematics, Y Y University, 65080 VAN, TURKEY 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1999年第4期40-48,共9页
Initial value problem for linear second order ordinary differential equation with small parameter by the first and second derivatives is considered. An exponentially fitted difference scheme with constant fitting fact... Initial value problem for linear second order ordinary differential equation with small parameter by the first and second derivatives is considered. An exponentially fitted difference scheme with constant fitting factors is developed in a uniform mesh, which gives first_order uniform convergence in the sense of discrete maximum norm. Numerical results are also presented. 展开更多
关键词 singular perturbation difference scheme uniform convergence initial value condition linear ordinary differential equation
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Line-element based nonlinear adaptive piecewise compensating correction for LVDT sensors
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作者 王立鹏 王军政 +1 位作者 赵江波 吴江丰 《Journal of Beijing Institute of Technology》 EI CAS 2013年第4期497-503,共7页
In order to solve the linear variable differential transformer (LVDT) displacement sensor nonlinearity of overall range and extend its working range, a novel line-element based adaptively seg- menting method for pie... In order to solve the linear variable differential transformer (LVDT) displacement sensor nonlinearity of overall range and extend its working range, a novel line-element based adaptively seg- menting method for piecewise compensating correction was proposed. According to the mechanical structure of LVDT, the output equation was calculated, and then the theoretic nonlinear source of output was analyzed. By the proposed line-element adaptive segmentation method, the nonlinear output of LVDT was divided into linear and nonlinear regions with a given threshold. Then the com- pensating correction function was designed for nonlinear parts employing polynomial regression tech- nique. The simulation of LVDT validates the feasibility of proposed scheme, and the results of cali- bration and testing experiments fully prove that the proposed method has higher accuracy than the state-of-art correction algorithms. 展开更多
关键词 line element adaptively segment linear variable differential transformer (LVDT) non-linear compensation correction
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